Apparatus for the automatic determination of a continuous bulk material throughput by a continuous balance

• US 5,024,352 A
• Filed: 02/22/1990
• Issued: 06/18/1991
• Est. Priority Date: 04/04/1985
• Status: Expired due to Fees

• Current Assignee: Buhler AG (Buhler Holding AG)
• Original Assignee: Sulzer AG
• Inventors: Kuhnemund, Bernd, Gmur, Bruno
• Primary Examiner(s): Shaver, Kevin P.
• Application Number:
  US07/484,351
• Time in Patent Office: 481 Days
• Field of Search: 222/77, 222/1, 222/55-58, 177/50
• US Class Current: 222/1
• CPC Class Codes: B29B 7/242 in measured doses
• CPC Class Codes: B29B 7/28 for measuring, controlling or regulating, e.g. viscosity control B29B7/242 takes precedence
• CPC Class Codes: B29B 7/60 for feeding, e.g. end guides for the incoming material B29B7/7615 takes precedence; feeding predetermined amounts for mixing in general B01F35/714
• CPC Class Codes: B29B 7/72 Measuring, controlling or regulating
• CPC Class Codes: G01G 11/003 Details; specially adapted accessories details of weighing apparatus in general G01G21/00; auxiliary devices for weighing apparatus in general G01G23/00
• CPC Class Codes: G01G 11/086 of the loss-in-weight feeding type
• CPC Class Codes: G01G 11/18 using digital counting
• CPC Class Codes: G01G 13/18 by valves or flaps in the container bottom
• CPC Class Codes: G01G 13/248 Continuous control of flow of material control of flow G05D7/00
• CPC Class Codes: Y10S 177/09 Scale bearings

Abstract

A method and apparatus for the automatic determination of a continuous bulk material through a continuous balance wherein a weighing vessel, an adjustable closure member movable in the weighing vessel for adjusting an outlet cross-section of the weighing vessel and an electronic weight difference measuring device are provided. The closure member provided in the outlet region of the vessel is so arranged that when the closure member is in the open operating position, there is a free mass flow in the weighing vessel and the bulk material flows freely and unhindered from the outlet of the weighing vessel. A control device is connected at its input to the weight measuring device and at its output to the adjustable closure member whereby a signal corresponding to the weight change in the weighing vessel per unit of time is produced, which is used for calculating the parameters of state of the bulk material flow.

Claims

1. Process for automatic determination of a bulk material flow throughput through a continuous balance and comprising the steps of feeding a bulk material into a weighing vessel of the continuous balance, providing an adjustable closure member in an outlet region of said weighing vessel as a movable wall part of said vessel and adjusting a size and a shape of an outlet opening of said weighing vessel by moving said adjustable closure member to position the adjustable closure member in said weighing vessel, said outlet region defining a substantially vertical pathway of said vessel for the bulk material flow and said movable wall part having a vertical component which partially defines said pathway;

providing measuring means on said vessel and measuring the weight of said weighing vessel while feeding the bulk material into the weighing vessel, controlling the throughput of bulk material by control means which operatively interconnect said weight measuring means and said adjustable closure member, and controlling the adjustable closure member to provide a continuous mass flow of material through of said weighing vessel while simultaneously measuring the weight of said weighing vessel.

2. Process according to claim 1, wherein said parameter signal is used for controlling the bulk material supply to an input to said weighing vessel.

3. Process according to claim 1, wherein the bulk material flow to said weighing vessel is interrupted during predetermined time intervals to determine the weight decrease of said weighing vessel and thereby determining the quantity of material flowing from said weighing vessel as a function of time.

4. Process according to claim 1, wherein, for compensating brief fluctuations of quantity of bulk material flowing to said weighing vessel, said weighing vessel is used as a compensating vessel.

5. Process according to claim 1, wherein said mass flow through said weighing vessel is briefly supplied to and collected in a second weighing vessel and further including the steps of establishing weight increase per unit time in said second weighing vessel due to bulk material flow therein, and calculating from the measured values of said second weighing vessel the bulk material quantity flowing through said first weighing vessel.

6. Process according to claim 1, wherein at least one determining parameter signal of the bulk material is derived from weight measurements in said measuring step.

7. Process according to claim 6, wherein said at least one determining parameter signal regulates a second product flow for mixing with said bulk material.

8. Process according to claim 6, wherein said at least one determining parameter signal controls a processing machine following said continuous balance.

9. Process according to claim 6, wherein said mass flow in said weighing vessel is briefly stopped by closing the outlet opening thereof, and wherein the increase in weight of the bulk material fed into said weighing vessel is determined.

10. Apparatus for automatic determination of throughput of a bulk material through a continuous balance, comprising:

a. a weighing vessel having an inlet opening for receiving bulk material and an outlet opening;

b. weight measuring means having an input and an output, said input being operatively connected with said weighing vessel;

c. adjustable closure means being positioned in an outlet region of said weighing vessel for closing and opening the outlet opening of said weighing vessel, said outlet region defining a substantially vertical pathway for the flow of bulk material, said closure means including a closure member forming an adjustable movable wall part of the weighing vessel, said closure means further including means for moving said closure member between a plurality of positions between opened and closed positions for adjusting said outlet opening of said weighing vessel to a shape and a size thereof to ensure, in its opened positions, a continuous mass flow of said bulk material through said weighing vessel;

said movable wall part of said closure member having a vertical component which partially defines said pathway for the flow of bulk material; and

d. control means having a program for controlling throughput of bulk material, said control means having an input and an output, said input of said control means being operatively connected with said output of said weight measuring means, while said output of said control means is operatively connected with said means for moving the closure member within said weighing vessel.

11. Apparatus according to claim 10, wherein said adjustable wall part is mounted for rectilinearly movement.

12. Apparatus according to claim 10, wherein said adjustable wall part is mounted for pivotal movement.

13. Apparatus according to claim 10, further including position indicating means connected with said movable wall part for indicating the position of the wall part.

14. Apparatus according to claim 10, wherein the closure member is mounted for pivotal movement and said means for moving adjusts said wall part at angles between 0°

and 40°

relative to a wall of said weighing vessel.

15. Apparatus according to claim 10, further including a dosing member positioned upstream of said weighing vessel and adapted for control by the continuous balance as a function of weight changes monitored by said weight measuring means.

16. Apparatus according to claim 10, further including a supply line and a removal line, wherein

a portion of said supply line is positioned at a distance above said weighing vessel;

a portion of said removal line is positioned at a distance below said weighing vessel;

passage zones of said portion of said supply line, said portion of said removal line and said weighing vessel have essentially the same cross section; and

said portions of said supply and removal lines and said weighing vessel are aligned with each other to form a feed line.

17. Apparatus according to claim 10, wherein said weighing vessel rests on said weight measuring means which are electronic weight measuring means.